1. Field
The present invention relates generally to implantable access ports and attachment mechanisms or systems for attaching the implantable access ports to a patient. More specifically, the present invention relates to implantable access ports with independent moving gears for the anchors, and related actuation devices.
2. Description of the Related Art
Implantable medical devices for performing therapeutic functions for a patient are well known. Such devices include pace makers, vascular access ports, injection ports (such as those used with gastric banding devices) and gastric pacing devices. Such devices are attached to a human, typically subcutaneously, in an appropriate place in order to function properly. It is desirable that the procedure to implant such devices be quick, easy, efficient, and require as small of an incision as possible.
A suture (also known as stitches) is typically used by doctors to hold skin, internal organs, blood vessels and all other tissues of the human body together after they have been severed by injury, incision or surgery. Suturing is both time consuming and inconvenient. Surgical fasteners, such as staples, clips, clamps, bands, tacks, or other wound or incision closure devices, have been used in surgical procedures to eliminate the need for suturing. Surgical fasteners are commonly used in surgical procedures to allow a surgeon to fasten, secure, and/or repair bodily tissue. In these applications, the surgeon often uses a fastener implanting device loaded with one or more surgical fasteners to accomplish in a few seconds what would have taken many minutes to perform by suturing. This reduction in operating time reduces blood loss and trauma to the patient.
Typically, such surgical fasteners have been used mainly for the closure of incisions or wounds, or to fasten tissues together. A surgical fastener that can be used with a number of different types of implantable medical devices would be beneficial for surgeons. Currently, surgical systems that incorporate surgical fasteners often use extremely specialized devices that may be unnecessarily complicated and are unsuitable for adaptation to other applications.
As a result, the majority of implantable medical devices are secured with sutures. For example, when inserting a gastric band and an associated access port, the associated access port may be sutured into place with 3 to 5 sutures against the rectus muscle sheath. Such placement of the sutures is often challenging because the associated access port is placed below several inches of bodily tissue (e.g., fat), and suturing the associated access port often takes as long as placing the gastric band itself. An improved fastening device would allow easy, one-step attachment with security equivalent to the sutured medical device.
One conventional method for fastening an implantable access port to the patient includes an external pistol-like applying means. The external pistol may include a trigger having geared teeth, a gear which meshes with the geared teeth, and a spring. The external pistol attaches to the implantable access port and tightens a fastener into the tissue of the patient upon pressing of the trigger. After attachment, the external pistol is removed from the implantable access port. Examples of similar methods may be found in European Patent Application Pub. No. 1736194 and U.S. Patent Application Pub. No. 2005/0283118.
Another conventional method for fastening an implantable access port includes fasteners extending from the housing of the implantable access port. In a self-attaching method, the implantable access port may be self-attached upon the surgeon applying a distal force to the access port housing, causing the fasteners to penetrate the tissue, engaging the tissue to hold the access port in place. Examples of similar methods may be found in U.S. Patent Application Pub. Nos. 2004/0254537, 2006/0190039, 2006/0235445, and 2009/0259190. In an electronic method, the fasteners may be electronically switched between a deployed position and an un-deployed position using an actuator.
European Patent Application Pub. No. 1543861 and U.S. Patent Application Pub. No. 2005/0131352 disclose an injection port that may be implanted using separate fasteners that are not part of the port prior to implantation. These fasteners are inserted one at a time using a tool. Thus, the tool is repositioned prior to implanting each fastener, which may lead to inefficiencies and inaccuracies in the implantation. U.S. Pat. No. 7,374,557 also discloses individually inserted fasteners.
The present invention overcomes at least some of the drawbacks of these conventional medical devices and methods.